Traffic into Mount Pleasant over the Ravenel Bridge was heavy during the evening rush hour, with some readers and users of social media reporting the backup was spilling over into peninsular Charleston.

Dispatchers at the Mount Pleasant and Charleston police departments said no wrecks were being worked in either jurisdiction, that traffic was just heavy.

Earlier today, three fire departments responded after a tractor-trailer caught fire in the eastbound lanes on the Don Holt Bridge, which carries Interstate 526.

No one was hurt by the fire, which took place about 2:30 p.m., but efforts to extinguish the blaze took about an hour and eastbound traffic was blocked.

Mark Ruppel, a spokesman for the Charleston Fire Department, said firefighters and vehicles from Charleston, St. Andrews Public Service District and North Charleston responded.

By about 3:30 p.m., emergency vehicles were clearing from the area and at least one of the eastbound lanes was reopened.